How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat brands, and we proudly install them on a frequent basis in West Chester. They’re durable and reliable. Plus, Honeywell is regularly improving its technology, bringing more features for your household.

Nevertheless, every thermostat can experience issues occasionally. That’s why we’ve put together this valuable guidebook to run through troubleshooting.

While you can typically repair most thermostat problems alone, they occasionally need Expert support. Our heating and cooling pros are available to help when you need us. We’re merely a call away at 484-401-7577.

Let’s begin the process by figuring out what model of thermostat your residence has.

What Kind of Thermostat Do I Have?

There are three models of thermostats:

  • Manual—This is the older dial-shaped thermostat. You won’t run into error codes with this one, but it’s also the least efficient for lowering energy costs.
  • Programmable—This thermostat features a digital screen and arrows you touch to determine your desired temperature. You can also choose daily programs to reduce the temperature when you’re gone and set it higher when you come home.
  • Smart—You won’t have to schedule any programs on this thermostat, since it learns your schedule. It automatically changes the temperature when you or loved ones are out and about to help you save on energy bills. You can also raise or lower the temperature anywhere on your phone or other Wi-Fi-enabled device. 

As you’re aware the majority of technologically advanced solutions, there are common glitches that might happen. Many of these problems don’t need professional assistance and are uncomplicated enough to repair alone.

Common Honeywell Thermostat Issues

Every thermostat has a unique kind of codes assigned to the troubles that happen.

Think how simple it can be to fix a computer by restarting it. For the most part, troubleshooting a thermostat can be just as uncomplicated.

Here is a listing the most reported Honeywell thermostat problems. These apply to the following programmable thermostats:

Display is Blank

If the display is empty on your programmable thermostat, you could need to install new batteries. If that doesn’t take care of the issue or you use a smart thermostat, there might be a wiring problem.

Next, you should make sure the power is enabled for your furnace or air handler. Make sure the switch near the indoor unit is switched “up”.

Additionally, you should confirm all furnace cabinet or air handler doors/panels are tightly in place.

An unsecured panel may trigger the safety switch, which stops power to the equipment.

Infrequently, an empty monitor might indicate you should buy a new thermostat.

Comfort Unit Won’t Turn On

Check that your thermostat is on “cool” or “heat,” not “off.”

During warm weather, verify you put the thermostat lower than the ambient temperature. When it’s cool, make sure it’s higher. This sounds absurd, but we’ve seen it happen lots of times.

Make sure the power switch close to your indoor equipment is in the “on” position. You should also make sure the cabinet doors or panels are closed on your furnace cabinet or air handler. A loose panel can trigger the safety switch, cutting off power to the system.

Unit still won’t start? Confirm circuit breakers haven’t flipped and that your HVAC unit isn’t displaying error codes.

“Cool On” or “Heat On” is Flickering

To start, make sure your thermostat is on “cool” or “heat.”

Then, ensure it’s signaling the right system to turn on. This is typically shown by “cool on,” “heat on” or a picture.

If this set of words or the picture is blinking, your thermostat is in a five-minute delay status. This setting protects your unit from harmful short cycling. This can happen if your power is interrupted.

Honeywell Thermostat-Specific Error Codes

Honeywell Lyric™ T5 Wi-Fi (RCHT8612WF/RCHT9510WFW)

  • 164—Heat pump requires service. Call Wesley Wood Service Experts at 484-401-7577 for support.
  • 168—Wi-Fi radio error. Reach Lyric technical support at 800-633-3991. 170—Internal memory error. Call Lyric technical support at 800-633-3991.
  • 171—Set date and time. Finalize these settings so scheduling can take place.
  • 173—Thermostat temperature sensor error. Reach Lyric technical support at 800-633-3991.
  • 175—AC power resumed. No action necessary.
  • 181/182—Put in a new air filter. Clear the display by hitting “dismiss” after installing a fresh filter.
  • 184—Replace humidifier pad. Clear the monitor by hitting “dismiss” after putting in a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the screen by touching “dismiss” after adding a clean filter.
  • 187—Clean or replace ventilator filter. Clear the monitor by touching “dismiss” after putting in a fresh filter.
  • 188/189—Get a new UV bulb. Ring Wesley Wood Service Experts at 484-401-7577 for assistance.
  • 210—Register online for outdoor temperature. Get the Lyric app to finish this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outside temperature. Download the Lyric app to do this step and ensure proper thermostat operation.
  • 399—No Internet. Check your network settings.
  • 400—No Wi-Fi signal. Wait for the thermostat to reconnect or select new Wi-Fi network.
  • 508—Wi-Fi not configured. Get the Lyric app and follow the steps to configure your thermostat.

For more specifics, look at this thermostat’s user manual.

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump requires service. Reach Wesley Wood Service Experts at 484-401-7577 for support.
  • 168—Wi-Fi radio error. Contact Wesley Wood Service Experts at 484-401-7577 for assistance.
  • 170—Internal memory error. Contact Wesley Wood Service Experts at 484-401-7577 for help.
  • 171—Set date and time. Finish these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Reach Wesley Wood Service Experts at 484-401-7577 for assistance.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Reach Wesley Wood Service Experts at 484-401-7577 for support.
  • 178—Outdoor temperature sensor error. Reach Wesley Wood Service Experts at 484-401-7577 for help.
  • 181/182—Get a new air filter. Clear the screen by touching “dismiss” after putting in a clean filter.
  • 183—Rinse humidifier tank and replace water filter. Clear the thermostat by tapping “dismiss” after doing these procedures.
  • 184—Install a new humidifier pad. Clear the thermostat by hitting “dismiss” after installing pad filter.
  • 185—Replace dehumidifier filter. Clear the thermostat by tapping “dismiss” after adding a new filter.
  • 186—Wash ventilator core. Clear the monitor by tapping “dismiss” after doing this task.
  • 187—Clean or replace ventilator filter. Clear the monitor by touching “dismiss” after buying a new filter.
  • 188/189—Add a new UV bulb. Contact Wesley Wood Service Experts at 484-401-7577 for help.
  • 210—Register online for exterior temperature. Get the Lyric app to finish this step and ensure correct thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Get the Lyric app to finish this step and ensure proper thermostat operation.
  • 399—No Internet. Check your network settings.
  • 400—No Wi-Fi signal. Wait for the thermostat to reconnect or select new Wi-Fi network.
  • 508—Wi-Fi not configured. Use the Lyric app and follow the procedures to connect your thermostat.

For more specifics, check this thermostat’s user manual.

Our Experts are Available to Provide Support

If you’re still experiencing troubles after working through the troubleshooting steps, our pros are ready to support you. Give us a call at 484-401-7577 and we’ll arrive quickly to determine the malfunction.

If you rely on an aging thermostat, today is a great time to think about a new device. Thermostat technology has come a long way in recent years Ask us for more information on how smart thermostats can make your residence more comfortable while helping save on utility expenses throughout the year.

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